1. Field of the Invention
This invention relates to an attitude detecting device for detecting the attitude of a camera by the use of a plurality of sensors, and to a multi-photo-metering apparatus using the same.
2. Related Background Art
The device disclosed in U.S. Pat. No. 4,364,650 is known as a camera attitude detecting device of this type. In that patent, there is shown an attitude sensor comprising mercury enclosed in a container and a plurality of sets of switches (sensors) having a pair of electrodes electrically connected together by the mercury, and one-dimensional attitude of the camera is detected by one of the pair of electrodes being ON.
Also, in Japanese Utility Model Application Laid-Open No. 61-143133, it is disclosed that when the direction of the optic axis is the x-axis and the horizontal direction orthogonal thereto is the y-axis and the vertical direction orthogonal to the x-axis and the y-axis is the z-axis, an attitude sensor is disposed within a camera so that the axial direction thereof is inclined with respect to any of the xy plane, the xz plane and the zy plane, whereby the switch state of the sensor is prevented from being indefinite.
In recent years, devices for detecting the three-dimensional attitude of a camera have been desired, and in this case, it is necessary to provide a plurality of sets of attitude sensors. Where, for example, three sets of such attitude sensors are provided, there are obtained 2.sup.3 =8 kinds of signals. However, if all of these eight kinds of signals are used as camera attitude information, the operation process thereafter will become unnecessarily complicated.
Also, where the attitude sensors are disposed with their axes inclined, the disposition space required therefor leads to bulkiness of the camera. Particularly, to incline the three sets of sensors in different directions, it is necessary to provide a large space.
The aforementioned U.S. Patent further discloses a multi-photometering apparatus of a camera for dividing the object field into a plurality of areas and photo-metering them to thereby determine a proper exposure value, and teaches therein the technique of changing the weighting in conformity with the attitude of the camera when finding a mean luminance value.
In the prior art, however, the data from each photometering element has been discriminated in conformity with respective camera attitudes detected. Therefore, where in an attempt to effect complicated discrimination, the mean value of the photometric data of the photometering elements is compared with the photometric data of the ground side of the object field and the photometric data of the middle portion of the object field or the photometric data of the sky side to thereby provide an exposure value conforming to a low luminance example or an exposure value conforming to the mean luminance, the attitude of the camera must first be discriminated and in each attitude, the above-mentioned comparison and exposure operation must be effected for all the photometric data. That is, there has been the problem that the outputs of the attitude sensors and the algorithm which determines the proper exposure are in unseparable and it is difficult to apply a complicated algorithm.